A number of fabric-forming methods have been developed over the years to produce profiled cross-section beams, such as T, L, Pi, H, I and U, either directly or indirectly, for manufacturing 3D (three-dimensional) fabric reinforced composite materials. Such 3D fabric reinforcements, called profiled beam-like pre-forms, are intended for primary load-bearing structural applications. These pre-forms, and other new types to be described herein, are together henceforth called 3D fabric items. The 3D fabric items which are like profiled beams are essentially composed of two sections: (i) the ‘vertical’ section/s, henceforth called web/s, and (ii) the ‘horizontal’ section/s, henceforth called flange/s. The simplest profiled beam-like 3D fabric items are exemplified by the “T” or “L” or “+” cross-sections as each one of them have one web and one flange. Other 3D fabric items, which are unlike profiled beams, can be more complex in structure and form, besides not necessarily comprising just webs and/or flanges, or even planar/linear webs and flanges.
In the context of the inventions being disclosed herein, some of the prior arts which are considered relevant for citing to lay the background include, for example, U.S. Pat. No. 5,429,853, U.S. Pat. No. 4,331,495, U.S. Pat. No. 6,103,337, U.S. Pat. No. 4,786,541, and U.S. Pat. No. 4,379,798, which relate to indirect production of profiled beam-like 3D fabric items by either stitching/joining different fabrics or folding/bending certain section/portion of suitably created fabric, and U.S. Pat. No. 5,021,281, U.S. Pat. No. 5,783,279, U.S. Pat. No. 5,121,530, U.S. Pat. No. 4,779,429, U.S. Pat. No. 4,686,134, U.S. Pat. No. 6,019,138, and WO91/06421, which relate to direct production of profiled beam-like 3D fabric items by specially developed processes. All these known methods represent the efforts spent over the years to solve an interesting but serious set of problems, which are described below through an example to put the shortcomings of existing 3D fabric items in proper perspective.
It has not been possible so far to manufacture, for example, a simple single-wall/layer “T” cross-section beam-like 3D fabric item, comprising yarns/tows/fibers/filaments/rovings/fibrous tapes etc., which are henceforth referred to as only yarns, with e.g. the following performance and function related features in a combined way:                A structurally integrated single-wall/layer web comprising yarns in +/−0° bias orientations relative to beam-like 3D fabric's length direction to bear shear/torsional forces;        A structurally integrated single-wall/layer flange comprising yarns in 0°/90° orientations relative to beam-like 3D fabric's length direction to bear tensile/compressive forces;        A mutual through-thickness connection of respective constituent yarns of the web and flange which intersect and integrate with each other at their junction to resist separation or delamination.        
In other words, it has not been possible to manufacture a profiled beam-like 3D fabric item wherein its web has, for example a braided structure, and the flange has, for example a woven structure, and the web and flange are interconnected to each other mutually in their thickness directions, i.e. the planes of web and flange intersect each other at their junction. Likewise, it has not been possible to manufacture a profiled beam-like 3D fabric item with its web having a woven structure, the flange having a braided structure, and the web-flange being interconnected to each other by their respective constituent yarns which mutually pass through the thickness directions of each other.
To be able to produce a delamination resistant composite material with relatively higher mechanical performance and improved functionality, and importantly a practically useable material in a cost effective manner, than is possible presently, it is imperative to combine different fabric architectural constructions, i.e. the characteristic arrangement of fibres/yarns created by individual fabric-forming processes, such as interlacing (i.e. woven by weaving) and intertwining (i.e. braided by braiding) because these fabrics have structurally integrated constructions and their use as webs/s and flange/s renders them stable and firm, and thereby the 3D fabric item self-supporting for enabling further processing satisfactorily and obtaining a superior composite material component. A textile preform with no/poor structural integrity collapses easily making its handling and impregnation with matrix difficult, besides causing fiber misalignments, improper fiber distributions, fiber breakages etc., which contribute to impair performance.
Still more importantly, it is imperative that the intersecting junction/s of the web/s and flange/s are well integrated by way of mutual through-thickness connection of the web/s and flange's through their respective yarns. Such a mutual through-thickness integrated junction of a 3D fabric item would be naturally unified and resistant to delamination/separation, and thereby improve the mechanical performance and reliability of the final composite material.
There does not appear to be any method available presently for practically, effectively and economically producing a 3D fabric item with the aforementioned characteristic fabric architectural or structural constructions. The prior arts cited above have been devised primarily to produce an elongate structure with more or less regular/uniform/homogenous architecture and form. These existing methods do not provide possibilities to produce 3D fabric items that have completely different structural architectures of the web/s and flange/s. Further, these methods do not provide either a web or a flange or both web and flange comprising a combination of different fabric architectures. Also, they are limited in terms of their ability to produce only either a specific or few varieties of forms/shapes and dimensions. As a consequence, these existing methods do not provide much scope in engineering complex 3D fabric items which require broad and deep performance and functional features. That these methods are ineffective is evidenced by the fact that they continue to remain industrially unsatisfactory and unattractive.
The indirect or stitching methods allow plying and stitching different 2D sheet-fabrics, and thereby enable combining different structurally integrated fabric architectures in the production of profiled beam-like products. However, there is no mutual through-thickness connection of the web and flange. The direct or special 3D fabric-forming processes provide through-thickness connection of web and flange, but do not produce a structurally integrated web (or flange), and both the web and the flange with relatively different fabric architectures. These two approaches are discussed below as neither of them is able to engineer the required performance and functional features in 3D fabric items. Also, as will be noticed they are practically complicated and inefficient. A suitable new solution is therefore required now to solve the problem at hand and it is made available through the inventions disclosed herein.
The methods of stitching/joining/stapling of different planar fabric sheets (which have been manufactured previously, or pre-produced, by employing suitable processes) to produce profiled beam-like 3D fabric items are indirect and exemplified by U.S. Pat. No. 5,429,853, U.S. Pat. No. 4,331,495, U.S. Pat. No. 6,103,337 and U.S. Pat. No. 4,786,541. By this ‘stitching’ approach the constituent yarns of the web/s and flange's of the resulting profiled beam do not intersect and pass in their respective mutual thickness directions at the web-flange junction. There is no intersection of the web/s and flange/s because different fabric sheets are curved/bent/folded/angled to enable assembling and stitching for shape formation of the cross-section. The absence of mutual through-thickness intersection of yarns at the web-flange junction, due to use of folded/curved fabric sheets, creates a void/empty ‘triangular’ space at the junction when other fabric strip/s are applied to bridge the disjointed section/s of the web/s-flange/s. Due to discontinuity of yarns between the mutual thickness-directions of the web/s and flange/s, the junction's are rendered weak. Composite materials comprising such 3D fabric items delaminate, i.e. fail by cracking and splitting. As a consequence, the stitched/joined materials tend to be unreliable and hence are unusable in high-performance applications.
An improvement over the stitching approach is reflected in U.S. Pat. No. 4,379,798 wherein a 3D fabric is produced with selectively built-in connected and disconnected section's or portion's. The disconnected section/s can be subsequently bent/folded in required directions for creating and obtaining the final shape. However, as with the stitched/joined materials, this material also does not create the web and flange which intersect in mutual through-thickness manner. As a consequence, the bent/folded section/s require additional connection and bridging through use of other textile materials to resist structural failure under forces/loads. However, such connecting and bridging of oppositely folded sections fail because of the void/empty ‘triangular’ space that is created at the web-flange junction, whereby the structure is rendered weak, prone to delamination, and hence unreliable.
Some other disadvantages associated with the stitching method include: (a) mismatch of fibre properties between those used for stitching and that constituting the fabric/s, (b) fibre material used for stitching being incompatible with the matrix used for making composite material, (c) relatively loose, shaky and weak junctions make the structure unreliable and difficult to handle and predict performance behavior, (d) lower reliability due to fibre breakages arising from handling and stitching action, (e) fibre displacements and direction misalignments arising from handling and stitching action, (f) being labour intensive and time consuming, (g) causing fibre waste generation, which adversely impacts the environment, (h) being expensive without providing real advantages, and (i) unsuitable for creating 3D fabric items with complex shapes.
Furthermore, to enable stitching, the thickness of the web/s and flange/s has to be kept relatively low, which in turn directly renders the obtained profiled material relatively lower in mechanical performance (due to relatively low amount of fibers) and hence unsuitable for heavy-duty applications. In any case, stitching/joining two fabrics does not overcome the fundamental problem of delamination arising from absence of a mutual through-thickness connection between web/s and flange/s at their junction/s.
The direct production methods, exemplified by U.S. Pat. No. 5,021,281, U.S. Pat. No. 5,783,279, U.S. Pat. No. 5,121,530, U.S. Pat. No. 4,779,429, U.S. Pat. No. 4,686,134, U.S. Pat. No. 6,019,138 and WO91/06421 also do not provide satisfactory and reliable 3D fabric reinforcements. This is because these processes have one or more of the following important shortcomings:                The web does not comprise one or more walls/layers of structurally integrated yarns in +/−θ° orientations.        The flange does not comprise one or more walls/layers of structurally integrated yarns in 0°/90° orientations.        The yarns of structurally integrated flange/s and structurally integrated web/s do not pass through thickness directions of each other.        The flange walls/layers are more than one layer thick.        The flanges are not composed of multiple individual/separate walls/layers.        The flanges are not made with yarns in +/−θ° orientations.        The web/s is not made with yarns in 0°/90° orientation.        The web/s and/or flange/s are not tapered along the exterior longitudinal edge sides.        The longitudinal inner corners of web-flange junction are not filleted/rounded.        The web/s is not composed of a combination of different architectures or orientation of yarns.        The flange/s is not composed of a combination of different architectures or orientation of yarns.        The web/s and/or flange/s do not have varying heights and widths, and non-planar and non-symmetric constructions.        3D Fabric items without web and flange are not producible.        3D Fabric items having curved form are not producible.        They cannot process a ready or pre-produced fabric together with yarns that are made into a suitable fabric and combine the pre-produced and just-produced fabrics to create a 3D fabric item.        
As can be noticed, these direct processes are unlike the indirect or stitching processes described earlier in that they do not use any ready or pre-produced suitable fabric/s that are structurally integrated to produce the required 3D fabric items. These processes cannot create a mutually intersecting junction of structurally integrated web/s and flange/s by using suitable pre-produced fabric/s of given architecture/s and a relatively different fabric architecture that is produced by integrating the yarns used in the process. These aspects will become clearer in the presentation below of the said prior arts.
Document U.S. Pat. No. 5,021,281 discloses profiled beam-like 3D fabric items wherein warp binding yarns (C) are incorporated in two bias angle (i.e. +/−θ° bias angle) orientations relative to the longitudinal direction of the web section of the indicated I-beam profile. However, these yarns (C) are not linked in any way to each other structurally, for example, intertwined, as happens in a braided fabric, but drawn linearly from a creel and trapped in a desired inclination in a plane (column 4, line 27-28) between the upper and lower flanges (A and B) (column 3, line 15-17) using healds (column 5, lines 40-44 and FIG. 9). Further, the yarns in the flange sections, which are oriented in 0° and 90° relative to the profiled material's longitudinal direction, are not interlaced in any way (column 5, line 18), as happens in weaving, but stacked and bound in respective flanges' thickness direction using other binding yarns (C1 and C2) as described therein (column 5, lines 20-22).
The +/−θ° bias yarns (C) in the web section occur without being mutually structurally linked in any way, i.e. the yarns (C) neither interlace (i.e. do not weave) nor intertwine (i.e. do not braid) nor interloop (i.e. do not knit), because there is no arrangement in the devised method for mutually integrating these yarns (C). Because of lack of any mutual structural connectivity/integrity between these (C) yarns, the web section remains as two separate sheets and hence unstable and prone to get easily disturbed and damaged. Further, the produced web section is an open structure like a trellis. It is not sufficiently filled with yarns to create a solid/undivided fabric plane. The deficiency of yarns makes the web resemble a truss structure, as can be noticed in FIGS. 8 and 9 therein. As a consequence, a web having a relatively low amount of yarns and without any structural integrity can neither accord performance nor be resistant to distortion during handling/further processing, such as matrix impregnation, and associated consequent damages. In fact such a limp web will tend to collapse under its own weight, as well as that of the upper flange's weight. Accordingly, realizing that such a textile structure is unsatisfactory in terms of dimensional stability and strength/rigidity, inclusion of hot-melting (i.e. thermoplastic) fibers has been suggested (column 4, lines 4-12) to join/bind the fibers for stabilization.
These shortcomings of the described process and material become abundantly self-clear when the profiled material's cross-section is considered to be T, instead of the illustrated I. The upper bends in the +/−θ° bias angle direction yarns (C) of the web (according to FIGS. 8 and 9) cannot be realized and supported in any way because there will be no flange, and hence no support to hold the +/−θ° bias yarns whereby the yarns of web will immediately collapse. Clearly, this method has extremely limited scope of applicability and usefulness.
As mentioned in document U.S. Pat. No. 5,021,281, the flanges of the I-beam profile are not interlaced (column 5, line 18). As a consequence and is represented in relevant Figures therein, each of the flanges is composed of three sets of yarns (11a-14a, 15a-18a, C1 and 11b-14b, 15b-18b, C2) each of which is running linearly in their respective directions (length, width and thickness). Such a non-interlaced architecture is technically unlike that of a conventional woven material which is composed of two sets of interlacing yarns (the warps and the wefts). With the yarns (11a-14a and 15a-18a), as also (11b-14b and 15b-18b), not being locked in positions by virtue of interlacing, the structure of the flanges tends to be unstable/non-rigid because its constituent yarns are displaceable easily. Such a structure thus does not provide the necessary structural stability/rigidity to the flanges.
Apart from the above limitations of the method according to U.S. Pat. No. 5,021,281, another important drawback of it is that it does not produce a profiled beam-like 3D fabric item with its surfaces at the longitudinal edges of either web/s or flange/s or both of these (depending on the profile's cross-section) with a taper to prevent concentration of stresses at the edges. Similarly, it does not produce a profiled beam-like 3D fabric item with filleted or rounded corners, where the surfaces of the web/s and flange/s meet, to prevent concentration of stresses at the corners.
Also, the foregoing method does not produce a profiled beam-like 3D fabric item wherein the web section has its constituent yarns in 0°/90° orientations and the flange section has its constituent yarns in +/−θ° bias orientations. Also, it neither produces a web with a combination of 0°/90° and +/−θ° orientated yarns, nor a flange with a combination of 0°/90° and +/−θ° orientated yarns. Further, this method does not produce the web/s and/or flange/s of multiple individual/separate but integrated layers. Also, this method cannot process any ready or pre-produced fabric in either its web/s or flange/s.
Document WO91/06421 proposes a profiled beam-like pre-form having a web portion and a flange portion. Referring to FIG. 1 therein, in the flange portion (1) at least two overlapping layers comprising parallel continuous fibers, or filaments, (4A/4B and 10) lie relatively in mutually right angle orientation, with the fibers (4A) of exterior layer oriented 90° to the longitudinal axis (3) of the pre-form. In the web portion (2) at least two layers of parallel continuous fibers, or filaments, (5A and 5B) lie relatively in mutually oppositely inclined angles orientation (‘diagonally’), between 30° and 80°, with respect to the longitudinal axis of the pre-form. These inclined yarns are not intertwined and integrated in any way whereby the two layers of web remain separated. The inclined or angle-oriented fibers (5A and 5B) constituting the web (2) bend/‘loop’ only around the 90° oriented fibers (4A) of the exterior layer of the flange portion (1).
Clearly, none of the layers (4A/4B and 10) of the fibers constituting the flange (1) are individually integrated in any manner. Similarly, none of the layers (5A and 5B) constituting the web (2) are individually integrated in any way. The only structural connection between the flange (1) and the web (2) is that of the fibers (5A and 5B) bending or ‘looping’ around the exterior fibers (4A). Accordingly, in the proposed pre-form all the constituent fibers in an individual layer run linearly in their respective direction of orientation. There is no structural integrity within any constituent layer by either interlacing or interlooping or intertwining the involved fibers. In fact the corresponding associated processes, namely knitting, weaving and braiding are stated therein to degrade the axial strength and stiffness of fibers and thereby unsuitable. Yet, interestingly, the produced pre-form is called a ‘woven’ pre-form (page 7)! As the pre-form itself has no structural integrity, the constituent fibers are prone to delamination, disorientation, and loosing fiber distribution and linearity. Such a pre-form would naturally easily disintegrate and collapse, for example during pultrusion process, even before being made into a composite material.
As can be understood now, the pre-form according to WO91/06421 also has the shortcomings discussed in respect of 3D fabric item of U.S. Pat. No. 5,021,281. In any case, this method also cannot process any pre-produced fabric in either its web/s or flange/s.
Document U.S. Pat. No. 5,783,279 also specifies a profiled beam-like 3D fabric material which is produced by interlocking the yarns (202 and 203) constituting the web (200) with those of the upper and lower flanges (101 and 102) as shown in FIGS. 4 and 5 therein (column 6, lines 50-53). The production of this 3D fabric item involves engaging the web yarns (202 and 203) between upper and lower flanges, by (a) either pulling out the web yarns (202 and 203) by force through use of a wedge-like former (30), which expands or separates the two flanges apart to the required distance, as shown in FIG. 16a (column 9, lines 11-25), or (b) by drawing out a specified length of the web yarns (202 and 203) and hooking them in a series of loops raised above the skin of the upper flange at longitudinally spaced intervals and hold them at required height (FIG. 16b), which will eventually help to produce the required height of the web. Subsequently, as the fabric production proceeds, the two flanges (101 and 102) are slid apart over the hooked web yarns (202 and 203) (column 9, lines 35-59). An alternative way to produce the same directly (i.e. without having to separate the flanges) is also indicated (column 9, line 63 to column 10, line 3) wherein rearrangement of some components is proposed.
In any case, the 3D fabric item produced according to the above method has the yarns (202 and 203) constituting the web (200) meander between the upper and lower flanges. They are interlocked with the yarns of the flange/s. These yarns constituting the web are themselves not mutually integrated into an intertwined structure, like that of a braid, and therefore this 3D fabric item is also unstable and cannot support itself. It will tend to collapse and hence get distorted and damaged easily. The flanges of this 3D fabric item are technically not interlaced/woven because, as can be noticed in FIGS. 4 to 8 therein, the longitudinal yarns (103 and 104) and transversal yarns (105 and 106) run linearly in their respective directions without the characteristic interlacing of yarns associated with the definition of weaving. (This structure is identical with that of U.S. Pat. No. 5,021,281.) If the flange is really woven in this case, then technically its weave pattern is unlike that of plain or any other weave. The web producible by this method is again a relatively trellis-like open construction resembling a truss structure whereby lack of sufficient yarns renders it directly lower in performance. Also, sliding the flanges (101 and 102) over the web yarns (202 and 203) to separate them apart to required distance will naturally cause mutual abrasion of the involved yarns which in turn will cause damage to the involved yarns and hence result again in lower performance. Such an action will also cause distortion of the structure and thereby cause corresponding reduction in performance and reliability.
Further, the other shortcomings discussed in connection with the 3D fabric item of U.S. Pat. No. 5,021,281 apply equally well to the 3D fabric item according to U.S. Pat. No. 5,783,279. Once again, this method also cannot process any pre-produced or ready fabric in either its web/s or flange/s.
Document U.S. Pat. No. 5,121,530 also specifies a method for producing profiled beam-like 3D fabric item (3). This method is also technically not weaving because the foremost operation of weaving process, namely shedding, simply does not exist. In this method the involved yarns (Y) are continuously and linearly laid repeatedly in desired different orientations, in a laminated or plied/stacked manner (i.e. layer by layer) without being interlaced/woven, in any technically established weave pattern, to achieve desired thickness of wall. The yarns concerned are laid between pre-arranged tubular guide pins (G) which are finally removed and in its place select yarns (Y), in a loop form, are incorporated to achieve binding of the laid linear yarns to obtain the final required product. (These production steps do not technically comply with the principle of weaving.) Although the produced structure is an improvement over the earlier attempts, it still suffers from being a homogeneous structure in both the web/s and flange/s besides having other shortcomings presented earlier. In any case, the web does not comprise +/−0° oriented yarns. Yet again, this method also cannot process any ready or pre-produced fabric in either its web/s or flange/s.
Document U.S. Pat. No. 4,779,429 also provides a method of producing profiled beam-like 3D fabric items, the structure of which is more or less similar to that shown in U.S. Pat. No. 5,121,530 above but considered knitted simply because knitting needles are used in production. Two mutually perpendicular sets of knitting needles, arranged parallel to each other in their respective sets alternately draw and lay yarns in their respective directions through a predisposed set of yarns (14) in required sections to create the cross-sectional shape of the profiled beam-like 3D fabric items. The created structure still suffers from being homogeneous in both the web/s and flange/s besides having other shortcomings presented earlier. In any case, the web does not comprise +/−θ° oriented yarns. Yet again, this method also cannot process any ready or pre-produced fabric in either its web/s or flange/s.
Document U.S. Pat. No. 4,686,134 also provides a profiled beam-like material (1) produced by impregnating or covering a core fabric (2) with a suitable agent such as resin or the like (3), and solidifying it, which aids the retention of the given shape. The web and flange of the core fabric (2) are integrated and formed by braiding a plurality of groups of yarns (4-6) as indicated (column 5, lines 15-21). Whereas yarns (6) extend longitudinally, the yarns (4 and 5) extend obliquely to cross each other at 60° (column 5, lines 22-30; FIG. 2). This arrangement of yarns (4-6) is achieved by using a “torchon” lace knitting machine having two tracks for moving bobbins of braid yarns (column 6, lines 45-51; FIGS. 7 and 8). As the braiding yarns (4 and 5) curve or bend at the edges of the profiled beam being produced, there is no possibility of it fraying before impregnation. The produced web and flange have the same homogeneous architecture besides lacking in many of the other requirements stated earlier. This method also cannot process any ready or pre-produced fabric in either its web/s or flange/s and connect them in their mutual thickness directions.
The method according to document U.S. Pat. No. 6,019,138 is devised to produce wall/s that extend outwardly from a base portion to create a stiffened panel. This method also does not technically comply with the principle of weaving because its working necessitates use of three mutually perpendicular sets of yarns (10, 12 and 14) as indicated (column 1, line 60 to column 2, line 2 and column 2, line 62 to column 3, line 4). Further, for this process to work, it is indispensable to use at least two layers of yarns (10) as pointed out therein (column 3. lines 15-17). Technically this process functions unlike the weaving process where only two sets of yarns (the warps and wefts) are needed and the warp yarns can be of either single or multiple layer types. Further, because this process is technically not weaving, the produced fabric's architecture does not correspond to any known weave pattern (plain, twill etc.). As can be noticed in FIGS. 3-5, the indicated yarns (12) are incorporated linearly, i.e. without any interlacing (same as indicated in U.S. Pat. No. 5,021,281). In any case, the web is not composed of +/−θ° bias angle yarns and the respective structures of the web and flange remain structurally homogeneous and identical. This method also lacks in creating the other performance requirements stated earlier. As with various methods discussed above, this method also cannot process any ready or pre-produced fabric in either its web/s or flange/s to produce the stiffened panels.
As can be observed now, another important practical limitation of these known methods is that they cannot produce 3D fabric beams such as profiled beams with relatively large cross-section areas and the fibre content that are typically needed for most applications. Further, these discussed methods cannot incorporate yarns/tows in a combination of different orientations in flange/s and web/s of a 3D fabric item. Further, these methods cannot produce a 3D fabric item, such as an I cross-section beam, wherein the two flanges have +/−θ° bias angular orientation of yarns and the web has its yarns oriented in longitudinal (90°) and lateral (0°) directions. Also, they cannot produce a 3D fabric item, such as an I-beam, wherein both the flange/s and the web/s comprise yarns in +/−θ° bias as well as longitudinal (90°) and lateral (0°) directions in required different sequential lay-up arrangements. Also, they cannot produce a 3D fabric item, such as an I-beam, wherein the yarns in one flange are arranged relatively differently in architecture compared with the arrangement of yarns in the other flange.
Further, none of these known methods, or their combinations, can produce complex 3D fabric items comprising web/s and flange/s such as those having combined curved-straight sections, bends, converging/diverging shapes, circular objects, varying dimensions in one or more directions, relatively inverted cross-sections, sine curved shapes etc. Clearly, 3D fabric items which are unlike profiled beams, and therefore do not necessarily comprise planar/linear webs and flanges, cannot be produced by these existing processes.
Further, all these known methods are not capable of handling and integrating a ready or previously produced fabric with the yarns used for producing a fabric in the process. In other words, they cannot produce a 3D fabric item by using a suitable pre-produced fabric of a given architecture and add it on, or combine it, in an integrated manner with the fabric being produced using yarns. By these known processes it is not possible to obtain integration of a pre-produced add-on fabric with a just-produced interacting woven fabric in their mutual through-thickness directions to create web/s and flange/s which mutually intersect at their junction's and directly result in a wholly integrated profiled beam-like 3D fabric item.
A person skilled in the art can infer now from the foregoing presentation that the presently available methods are insufficient, inefficient and incapable of producing truly advanced and complex 3D fabric items, for meeting the increasing mechanical performance and reliability demands of emerging high-performance composite materials, practically and in a cost effective manner.
Accordingly, there is still a need for improvements in respect of methods and apparatuses for producing 3D fabric items, and in respect of such produced 3D fabric items.